What are the causes of a bent valve pushrod?
2 Answers
The causes of a bent valve pushrod are: the valve is obstructed during its return or momentarily contacts the piston; unauthorized modifications to the vehicle's exhaust system result in reduced backpressure. Without readjusting the valves, this leads to exhaust valve blow-by, where instantaneous adhesion to the valve seat causes the pushrod to bend. 1. Symptoms of damaged car valves include: reduced engine efficiency and decreased vehicle power; abnormal noises, unstable idling or poor acceleration during engine operation, diminished overtaking performance, and in severe cases, difficulty starting the engine or failure to ignite, along with increased air leakage or carbon buildup. 2. Additional information: In water-cooled engines, the cylinder block and crankcase are often cast as a single unit, referred to as the cylinder block-crankcase or simply the cylinder block. Typically made of gray cast iron, the upper cylindrical cavities of the cylinder block are called cylinders, while the lower part supports the crankshaft and provides space for its movement. The interior of the cylinder block is reinforced with numerous ribs and includes cooling water jackets and oil passages.
I remember one time I drove too aggressively, braking hard after high speed, and suddenly heard a "click" sound from the engine. The mechanic later told me the valve pushrod was bent. This is usually caused by mechanical impact, such as internal piston and valve collisions during intense movement, or timing chain slack leading to misalignment and subsequent impacts. Excessive load and vibration are also contributing factors, like engine overheating or aging components. I later learned to drive more smoothly, avoiding hard acceleration during startup, and now rarely encounter such issues. Regular maintenance, such as checking the timing system and lubrication, can effectively prevent bending. A healthy engine ensures peace of mind while driving—safety first.
